Self propelled pinking device

ABSTRACT

A hand held power driven pinking cutter having a rotary pinking blade driven by a worm and worm wheel arrangement from an electric motor. The pinking blade cooperates with a complimentary rotary anvil to drive the same and to cut a pink edge on fabric material placed therebetween. An endless belt positioned about two guide rollers on opposite sides of the anvil is driven by frictional contact with the rotary anvil to drive the device forwardly at substantially the same speed at which the cutting action is taking place. The endless belt may have molded projections or spikes extending from the surface thereof and cooperate with complementary depressions in the anvil such that the frictional contact between the belt and the anvil is substantially great. The blade may be imbedded between resilient members to increase the frictional contact between the blade and the anvil.

- Cowdrey is] 3,668,780 [4s] June 13, 1972 SELF PROPELLED PIN KING DEVICE Primary Examiner-Theron E. Condon Attamey-Marshall .l. Breen, Chester A. Williams. Jr. and Alan Ruderman ABSTRACT from an electric motor. The pinking blade cooperates with a [72] Inventor: Roy M. Cowdrey, Lake Hiawatha, NJ.

[73] Assignee: The Singer Company, New York, NY. [22] Filed: Oct. 8, 1970 I [21] Appl. No.: 79,150

[52] US. Cl ..30/178, 30/180, 30/264, 1 30/273 [51] Int. Cl. ..B26b 25/00 [58] Field of Search .....30/178, 179. 180, 230, 264, 30/273, 275, 276

[56] References Cited UNITED STATES PATENTS 2,200,746 5/1940 Hoskwith ..30/275 2,861,340 11/1958 Hazzard ..30/178 2,578,346 12/1957 Florian et a1... .....30/l78 45 7,899 8/1891 Elliott ..30/273 complimentary rotary anvil to drive the same and to cut a pink edge on fabric material placed 'therebetween. An endless belt positioned about two guide rollers on opposite sides of the anvil is driven by frictional contact with the rotary anvil to drive the device forwardly at substantially the same speed at which the cutting action is taking place. The endless belt may havemolded projections or spikes extending from the surface thereof and cooperate with complementary depressions in the anvil such that the frictional contact between the belt and the anvil is substantially great. The blade may be imbedded between resilient members to increase the frictional contact between the blade and the anvil.

7 Claim, 4 Drawing figures IN VENTOR.

R0 y M. Cowdre y BY TN SS= if l -v WI W? W ATTORNEY BACKGROUND OF THE INVENTION This invention relates to hand held power cutting tools and more particularly to a hand held electric power driven pinker for cutting a serrated edge in a cloth or other fabric material.

The use of a pinking shear to obtain a saw-tooth or zigzag border or line of severance when cutting cloth fabric is a well known expedient to' eliminate unraveling of the yarns or threads along the edges of certain materialsthat would occur when a straight edge cut is provided. Power pinking cutters are known in the art which provide a serrated rotating blade acting in cooperation with an anvil or backing member. However, to properly cut, it is critical that the cutter be fed intothe material at the correct rate as the cutting operation proceeds. If the rate of feed is too slow, the fabric is gripped and pulled between the blade and the anvil and is pulled off the surface of the table upon which is lying. This tends to give wrinkles to the material and effects the shape and contour of any pattern that is being cut. Furthermore, if the cutter is not properly fed along the line of cut of the fabric, that is, at a rate fast enough to keep pace with the-rotation of the cutting blade, the fabric tends to be recut. With a straight edge cutter this is of no importance, but with a pinking cutter having a serrated blade the recutting of zigzag edges effects the peaks and valleys of the pinked edge. Thus, each time the teeth of the pinking blade recut the pinked edge the saw tooth pattern tends more closely to approach a straight line edge with its incipient disadvantages. If the cutter is fed too fast over the work as the cut progresses. the fabric again tends to get wrinkles and as the cutter operates over the wrinkled portion of the fabric, it cuts the wrinkles and results in a completely inadequate product. With a lot of practice an operator of a pinking device of this type can learn to-feed the cutter at the same rate as the cut is progressing thereby to obtain the proper pinking out. However, before becoming proficient in the operation of a pinking cutter of this type a large amount of wasted material may be generated.

SUMMARY OF THE INVENTION The present invention overcomes these deficiencies of the prior art pinking cutters by providing a self propelled drive for moving the cutter forwardly at precisely the same speed as the blade is rotating, that is, at the same speed at which the cutting action is taking place. In theparticular embodiment disclosed, this invention utilizes. an endless belt which is frictionally driven by direct engagement withtheanvil and is-adapted to set upon a table like surface to drive the cutting unit forwardly. inasmuch as the anvil is driven by direct engagement with the cutting edge of the blade, and at the same speed thereof, the belt is driven at substantially the same speed as the cutting edge, and, therefore, the unit is propelled forwardly along the table surface at the same speed as the cutting action is taking place. This maintainsthe proper registration of the pinking edge to prevent recutting thereof, and further maintains the proper relationship between cutting speed and material feed to prevent wrinkles and other undesirable effects from occuring in the material to be cut. I

Accordingly, it is a primary object of this invention to provide a hand held power pinking cutter in which the material is fed at substantially the same relative speed as cutting is occurring.

Another object of this invention is to provide a power driven hand held pinking cutter which is propelled fonvardly along a table-like surface at the same rate at which material is being cut.

A still further object of this invention is to provide a hand held power pinking cutter having a flexible endless belt driven by a rotary anvil and adapted to engage a table-like work support surface to drive the cutter forwardly at the same speed at which the blade is cutting material fabric between the blade and the anvil.

BRIEF DESCRIPTION OF THE DRAWINGS The particular features and advantages of the invention, as well as other objects, will become apparent from the following description taken in connection with the accompanying drawings, in which:

FIG. 1 is a perspective view of a hand held power pinker incorporating one embodiment of the present invention, partially broken away and partially in section showing the means for propelling the unit forwardlyatthesame speed at'which the cutting occurs;

ing more positive transfer of motion from the anvil to the belt;

and

FIG. 4 shows a modified form of the blade for providing a more positive transfer of motion from the blade to the anvil.

' DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring now'to the accompanying drawings wherein like reference numerals denotes similar parts throughout the several views there is disclosed a hand held power pinker designated generally as 10 and comprising a substantially cylindrical housing 12 to which an annular collar 14 is secured by means of set screws 16. The collar has an annular disc (not shown) molded integraltherewith to which a yoke member 18 is secured by means of screws 20. The yoke member is substantially circular at the upper portion thereof and includes a central aperture 22 in the circular portion. A downwardly extending portion 24 is formed tangentially downwardly at one side of the circular portion and tapered downwardly from the other side thereof. Secured to the downwardly extending portion by means of a screw 26 is an upstanding portion 28 of a support standard 30. The standard comprises two substantially parallel legs 32, 34 connected by a cross member 36 to form a bifurcated roller support. The upstanding portion 28 is integral with the cross member 36 and atthe upper extremity thereof includes a bracket arm 38 which overlays and is substantially parallel to leg 32.

Mounted within the housing 12 is an electric motor 40 which may be selectively powered from rectified reduced household alternating current plugged into adoptor 42 or from rechargeable batteries mounted in the housing and charged from a household outlet through theadoptor 42. The motor, through reduction gearing 44, drivesa shaft 46 which extends out the front of the housing through the aperture 22 in the yoke member, and which has threaded at its free'end a worm gear 48. Secured to the bracket arm 38 by means of set screws is one end of a stud shaft 50. A blade wheel 52 having a continuous serrated cutting edge 54 forming a multiplicity of cutting teeth, a bushing 56 on each side thereof, and a worm wheel 58 are joumaled on the shafi 50. The worm wheel is positioned adjacent one of the bushings 56 and in meshing engagement with the worm so as to be driven thereby. The blade, the two bushings (only one of which is illustrated) which act as spacers, and the won'n wheel are keyed together by pins (not shown) so as to rotate as a unit. Secured to the stud shaft by a set screw 60 adjacent the worm wheel is a collar 62 which maintains and prevents axial shifting of the worm wheel, the blade and the bushings on the shaft. It is thus clear that as the motor drives through the reduction gearing the worm rotates the worm wheel together with the bushings and the serrated blade.

Extending transversely between and secured to the bifurcated legs 32 and 34 are three substantially parallel shafts 64, 66 and 68. Joumaled for free rotation about the shaft 64 is a cylindrical platen or anvil 70, preferably of metal, which abuts or presses against the cutting edge 54 of the blade in an interference type of fit so as to cooperate with the blade to cut material fed therebetween. Of course the serrated shape of the cutting edge acting against the cylindrical anvil as a backing member cuts a zigzag or pinking edge or border on any fabric material passing therebetween. The shafts 66 and 68 are mounted on opposite sides of the anvil shaft 64 and slightly below its centerline. Journaled for free rotation about each of the shaft 66 and 68 is a respective roller or pulley 72 and 74 having spaced flanges separated by a central portion. Mounted about-the central portion of each roller is a flexible endless belt 76 which passes beneath the cylindrical anvil and is frictionally engaged thereby. The position of the shafts 66 and 68 and the roller diameter is such that the lower portion of the belt is positioned to be presented onto a work support surface or table 78.'The anvil shaft 64 includes an eccentric screw 80 which mounts in the legs 32 and 34, thus, turning of the screw 80 provides for adjusting the contact pressure between the cutting edge 54 and the anvil 70. It should thus be clear that as the worm rotates the worm wheel and thus the blade, the anvil is rotated by engagement with the blade cutting edge in the direction opposite to the rotation of the blade and imparts to the belt 76 and the rollers 72 and 74 a rotational motion in the same direction as the rotation of the blade. Thus, the bottom-portion of the belt, which when the unit is operated upon table-like work support surface 78, propels the pinking unit forward in the same rate at which the cutting takes place between the cutting edge and the anvil. Therefore the cutter is fed relative to the material at substantially the same speed as severance occurs.

Secured to the yoke is a spring metal guard 82 which includes at its forward'cnd two bifurcated'fingers 84 and 86. ()nt: of the fingers 84 protects the material fed between the cutting blade and theanvil-from engagement with the worm wheel while the other finger 86 protects the material from ongagement with the bracket arm side of the cutter, i.e';, a lubrication area. The upstanding portion of the standard includes a relieved area 88 which acts as a snowplough so that material after being cut can freely flow beyond the blade without bunching up. To prevent engagement with the material and the belt there is provided a guard 90 overlaying the front roller 72 and a guard 92 overlaying the rear roller 74. A support base 94 is secured by screws (not shown) to the legs 32 and 34 of the standard 30.so as to aid in supporting the device and to nose under-the fabric to be cut. A cover 96 is secured to the yoke 18 to protect against the operator inadvertantly touching the blade with her hand. .Thus only the leading edge of the base 94 and the cutter and anvil engage the material, so that a clean cut may be made andthe feeding of the material is not interfered with by any of the other moving components.

In order to increase the frictional engagement between the belt and the anvil so as to provide a more positive transfer of motion from the anvil to the belt, the belt may be molded with a multiplicity of upstanding spikes 100 equally spaced along the surface of each edge. FIG. 3 shows this modification and further illustrates an anvil having complimentary slots or depressions 102 equally spaced about the surface thereof for receiving these spikes so that as the anvil rotates the cooperation between the spikes and the slots results in a positive transfer of the motion of the anvil to the belt. 1

To provide a more positive transfer of motion from the blade to the anvil the blade may include the modified con- It is thus clear that a simple yet effective hand held power pinking device is disclosed which feeds itself forwardly in the direction of the uncut material along the line of cut thereof at the same rate at which cutting is progressing thereby providing a proper pinking cut. This specification however includes detail which are for purposes of illustration only as it will be apparent for those skilled in the art that numerous changes may be made in those details without departing from the spirit and principles of the invention.

Having thus set forth the nature of the invention, what I claim herein is: I

1. In a power pinking device having a frame, a cutting blade having a serrated cutting edge, means for rotatably mounting said blade on said frame, power drive means for selectively rotating said blade, an anvil providing a backing surface against which the cutting edgemay operate to sever a zigzag border on fabric inserted therebetween, and means for rotatably mounting said anvil on said frame in abutting relationship with said cutting edge to be rotatedthereby, the improvement comprising, propelling means operatively driven by said anvil in the direction of rotation of said blade and at substantially the same speed as that of said cutting edge and adapted to engage a fabric work support surface for propelling said device on said support surface at substantially the same speed as fabric severance is occurring. I

2. In a pinking device as recited in claim 1 wherein said propelling means comprises a flexible' endless belt, guide means for supporting said belt in frictional engagement with said anvil and in position permitting engagement thereof with said work support surface, and means for rotatably mounting said guide means on'said frame. I

3., In a pinking device as recited in claim 1 wherein said propelling means comprises a flexible endless belt, a pair of guide rollers rotatably supported on said frame on opposite sides of said anvil, said belt being disposed about said rollers and in frictional engagement with said anvil, said rollers further being disposed so as to present said belt to said work support surface. 7

4. In a pinking device as recited in claim '3 wherein said anvil includes a multiplicity of depressions equally spaced about the surface thereof, and said belt is formed with a multiplicity of upstanding projections spaced along the surface thereof'and separated one from the other a distance equal to the separation between the depressions on said anvil, said depressions being disposed for cooperative engagement-with said projections to provide a positive transfer of motion from said anvil to said belt.

5. A hand held power pinking device adapted to operate upon a work support surface to sever a web of textile material, said device comprising a frame, a rotatable cutting knife mounted on a fixed axis on said frame, said knife having pinking teeth means, means operativeto effect cutting movement of said knife, a substantially cylindrical platen rotatably mounted on said frame in driving engagement with said knife teeth to be rotated thereby and to press the web against said teeth means during the cutting movement of said knife to form a pinked cut edge in said web, and means driven by said platen and mounted on said frame in frictional engagement with the work support surface for advancing said device relatively to struction shown in FIG. 4. The blade is there imbedded said web in the direction of unsevered material.

6. A hand helcl'power pinking device asrecited in claim 5 wherein said means for advancing said device comprises a flexible endless belt, and means for mounting said belt in frictional engagement with said platen.

7. A hand held power pinking device as recited in claim 5 wherein said means for. advancing said device comprises a flexible endless belt, a pair of guide rollers rotatably supported on said frame on opposite side of said platen, said belt being disposed about said rollers and in frictional engagement with said platen, said rollers further being disposed so as to frictionally present said belt to said work support surface. 

1. In a power pinking device having a frame, a cutting blade having a serrated cutting edge, means for rotatably mounting said blade on said frame, power drive means for selectively rotating said blade, an anvil providing a backing surface against which the cutting edge may operate to sever a zigzag border on fabric inserted therebetween, and means for rotatably mounting said anvil on said frame in abutting relationship with said cutting edge to be rotated thereby, the improvement comprising, propelling means operatively driven by said anvil in the direction of rotation of said blade and at substantially the same speed as that of said cutting edge and adapted to engage a fabric work support surface for propelling said device on said support surface at substantially the same speed as fabric severance is occurring.
 2. In a pinking device as recited in claim 1 wherein said propelling means comprises a flexible endless belt, guide means for supporting said belt in frictional engagement with said anvil and in position permitting engagement thereof with said work support surface, and means for rotatably mounting said guide means on said frame.
 3. In a pinking device as recited in claim 1 wherein said propelling means comprises a flexible endless belt, a pair of guide rollers rotatably supported on said frame on opposite sides of said anvil, said belt being disposed about said rollers and in frictional engagement with said anvil, said rollers further being disposed so as to present said belt to said work support surface.
 4. In a pinking device as recited in claim 3 wherein said anvil includes a multiplicity of depressions equally spaced about the surface thereof, and said belt is formed with a multiplicity of upstanding projectIons spaced along the surface thereof and separated one from the other a distance equal to the separation between the depressions on said anvil, said depressions being disposed for cooperative engagement with said projections to provide a positive transfer of motion from said anvil to said belt.
 5. A hand held power pinking device adapted to operate upon a work support surface to sever a web of textile material, said device comprising a frame, a rotatable cutting knife mounted on a fixed axis on said frame, said knife having pinking teeth means, means operative to effect cutting movement of said knife, a substantially cylindrical platen rotatably mounted on said frame in driving engagement with said knife teeth to be rotated thereby and to press the web against said teeth means during the cutting movement of said knife to form a pinked cut edge in said web, and means driven by said platen and mounted on said frame in frictional engagement with the work support surface for advancing said device relatively to said web in the direction of unsevered material.
 6. A hand held power pinking device as recited in claim 5 wherein said means for advancing said device comprises a flexible endless belt, and means for mounting said belt in frictional engagement with said platen.
 7. A hand held power pinking device as recited in claim 5 wherein said means for advancing said device comprises a flexible endless belt, a pair of guide rollers rotatably supported on said frame on opposite side of said platen, said belt being disposed about said rollers and in frictional engagement with said platen, said rollers further being disposed so as to frictionally present said belt to said work support surface. 